PRESS RELEASES

BEIJING, March 14, 2018 (GLOBE NEWSWIRE) -- 21Vianet Group, Inc. (Nasdaq:VNET) ("21Vianet" or the "Company"), a leading carrier-neutral Internet data center services provider in China, today announced that the Company and Microsoft Corp. ("Microsoft") have agreed to extend their partnership to provide world-class public cloud services to Chinese customers.

Combining Microsoft's global technological leadership and 21Vianet's outstanding local operations, Microsoft Azure and Office 365 operated by 21Vianet have achieved an unanticipated and robust three-digit growth for nearly four consecutive years in China, successfully providing Azure public cloud services to more than 100,000 Chinese enterprise customers, and attracting over 1,300 cloud partners and over 100,000 active Azure DevOps developers; meanwhile 1.2 million Chinese enterprise users and 20 million educational users currently conduct their daily work using Office 365. This breakthrough cooperation model pioneered by Microsoft and 21Vianet has been recognized as an effective and successful method for a legal and compliant operation of international cloud services in
China.

Josh Chen, 21Vianet Founder and Chairman said, "The fruitful collaboration between 21Vianet and Microsoft to introduce Azure and Office 365 to China has been well proven by our business success over the last four years. 21Vianet has been recognized as a reliable local operator with whom to run network, data center, and cloud services. Together with Microsoft, we are providing world-leading, qualified, trustworthy, and intelligent cloud services to Chinese customers. With our agreement now extended, we will continue to invest more in providing ever-evolving cloud services to our mutual customers."

Alain Crozier, Microsoft Corporate Vice President, Chairman and CEO of Greater China Region, said, "Digital
transformation powered by technological innovation is unveiling significant opportunities for businesses in every industry. China, with its clear strategy of innovation-driven development, possesses unique strengths that will allow it to win with the new industrial revolution. With years of successful operations behind us, we are confident of our strong partnership with 21Vianet and of the unique business model we have created. We believe in the long-term potential of the China market, which is why we want to reconfirm our commitment and are extending our agreement with 21Vianet."

Announced in 2013 and officially launched in March 2014, Microsoft Azure operated by 21Vianet is the first international public cloud service generally available in
the China market. Customers and partners range from established Chinese brands such as Haier, Lenovo, and Huawei to emerging powerhouses such as smartphone manufacturer Xiaomi, bike-share company Mobike, automobile manufacturer BYD, world-leading sporting goods company Amer Sports and Arcplus Data & Innovation Technology, an integrated solutions provider for construction engineering industry.

Office 365 operated by 21Vianet was launched in China in April 2014 and now ranks # 1 in China's SaaS market. Huawei, Tencent, and Pactera currently use Office 365 operated by 21Vianet to empower their employees and
optimize their daily business operations.

Since its establishment in 2013, 21Vianet's cloud operation and maintenance group for Azure and Office 365 in China has grown from dozens of people to one of the largest professional cloud operation and maintenance teams in China, and more than half of the current staff members are senior engineers. With user satisfaction over 98%, Microsoft Azure and Office 365 operated by 21Vianet have been widely recognized in the industry and have received 10 trusted cloud certifications, including cloud hosts, cloud storage, databases, cloud engines, network load balancing, enterprise-class e-mail, file sharing, online meeting, cloud backup and hybrid cloud, making 21Vianet the cloud service provider with the most trusted cloud
certifications in China. In 2017, Microsoft Azure operated by 21Vianet, passed the industry's first "Hybrid Cloud Solution Assessment" and was awarded the only "Trusted Cloud Technology Innovation Award-Hybrid Cloud Award" by the Trusted Cloud Conference. In accordance with the latest regulatory requirement on cloud services, 21Vianet, as the operator, obtained the newly required Internet Resource Collaboration Service (IRCS) license in August 2017, which ensures the compliance of its cloud services in China.

With a growth mindset and strong confidence in the China market, 21Vianet and Microsoft are in the process of expanding their capacity. As Microsoft CEO Satya Nadella announced at the Microsoft Tech Summit 2017 in November, Microsoft Azure operated by 21Vianet will triple its capacity in China in the beginning of 2018. Azure's enlarged capacity will provide increased flexibility and wider access to cutting-edge Azure cloud services. It will also make it easier for multinational companies to meet the needs of Chinese customers through the scale, power, and secure infrastructure of the Azure cloud.

21Vianet Group, Inc. is a leading carrier-neutral Internet data center services provider in China. 21Vianet provides hosting and related services, cloud services, and business VPN services, improving the reliability, security and speed of its customers' Internet infrastructure. Customers may locate their servers and networking equipment in 21Vianet's data centers and connect to China's Internet backbone through 21Vianet's extensive fiber optic network. 21Vianet operates in more than 30 cities throughout China, servicing a diversified and loyal base of more than 4,000 hosting enterprise customers that span numerous industries ranging from Internet companies to government entities and blue-chip enterprises to small- to mid-sized enterprises.

About
Microsoft

Microsoft (Nasdaq "MSFT" @microsoft) enables digital transformation for the era of an intelligent cloud and an intelligent edge. Its mission is to empower every person and every organization on the planet to achieve more.

Safe Harbor Statement

This announcement contains forward-looking statements. These forward-looking statements are made under the "safe harbor" provisions of the U.S.Private Securities Litigation Reform Act of 1995. These statements can be identified by terminology such as "will," "expects," "anticipates," "future," "intends," "plans," "believes," "estimates" and similar statements. Among other things, quotations from management in this announcement as well as 21Vianet's strategic and operational plans contain forward-looking statements. 21Vianet may also make
written or oral forward-looking statements in its reports filed with, or furnished to, the U.S. Securities and Exchange Commission, in its annual reports to shareholders, in press releases and other written materials and in oral statements made by its officers, directors or employees to third parties. Statements that are not historical facts, including statements about 21Vianet's beliefs and expectations, are forward-looking statements. Forward-looking statements involve inherent risks and uncertainties. A number of factors could cause actual results to differ materially from those contained in any forward-looking statement, including but not limited to the following: 21Vianet's goals and strategies; 21Vianet's expansion plans; the expected growth of the data center services market; expectations regarding demand for, and market acceptance of, 21Vianet's services; 21Vianet's expectations
regarding keeping and strengthening its relationships with customers; 21Vianet's plans to invest in research and development to enhance its solution and service offerings; and general economic and business conditions in the regions where 21Vianet provides solutions and services. Further information regarding these and other risks is included in 21Vianet's reports filed with, or furnished to, the Securities and Exchange Commission. All information provided in this press release and in the attachments is as of the date of this press release, and 21Vianet undertakes no duty to update such information, except as required under applicable law.